Revert "Make sure that the frame dispatch returns a non-null value fo…

…r job.str_os"

This reverts commit fda4f0d

cuebot/src/main/java/com/imageworks/spcue/dao/postgres/FrameDaoJdbc.java

@@ -331,7 +331,7 @@ public DispatchFrame mapRow(ResultSet rs, int rowNum) throws SQLException {
             frame.minGpuMemory = rs.getLong("int_gpu_mem_min");
             frame.version = rs.getInt("int_version");
             frame.services = rs.getString("str_services");
-            frame.os = Optional.ofNullable(rs.getString("str_os")).orElse("");
+            frame.os = rs.getString("str_os");
             frame.lokiEnabled = rs.getBoolean("b_loki_enabled");
             frame.lokiURL = rs.getString("str_loki_url");
             return frame;